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Trophic transfer of nanomaterials and their effects on high-trophic-level predators
NanoImpact, 2023Nanotechnology offers great opportunities for numerous sectors in society. One important challenge in sustainable nanotechnology is the potential of trophic transfer of nanomaterials (NMs), which may lead to unintentional impacts on environmental and human health.
Fei, Dang +4 more
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Predator signaling of multiple prey on different trophic levels structures trophic cascades
Ecology, 2023AbstractThe capacity of an apex predator to produce nonconsumptive effects (NCEs) in multiple prey trophic levels can create considerable complexity in nonconsumptive cascading interactions, but these effects are poorly studied. We examined such effects in a model food web where the apex predator (blue crabs) releases chemical cues in urine that affect
Benjamin A. Belgrad +2 more
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TROPHIC LEVELS AND TROPHIC TANGLES: THE PREVALENCE OF OMNIVORY IN REAL FOOD WEBS
Ecology, 2007The concept of trophic levels is one of the oldest in ecology and informs our understanding of energy flow and top-down control within food webs, but it has been criticized for ignoring omnivory. We tested whether trophic levels were apparent in 58 real food webs in four habitat types by examining patterns of trophic position.
Ross M, Thompson +3 more
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Direct and indirect trophic effects of predator depletion on basal trophic levels
Ecology, 2016AbstractHuman population growth and development have heavily degraded coastal ecosystems with cascading impacts across multiple trophic levels. Understanding both the direct and indirect trophic effects of human activities is important for coastal conservation. In New England, recreational overfishing has triggered a regional trophic cascade.
Huili, Chen +3 more
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Modelling of predator–prey trophic interactions. Part I: two trophic levels
Journal of Mathematical Biology, 2005A class of lumped parameter models to describe the local dynamics in a controlled environment of a two-trophic chain is considered. The class is characterized by a trophic function (functional response of predator to the abundance of prey) depending on the ratio of prey biomass x and a linear function of predator biomass y: f(qx/[(1-rho)k + rhoy ...
BUFFONI G. +3 more
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Modelling of predator–prey trophic interactions. Part II: Three trophic levels
Journal of Mathematical Biology, 2006A general class of lumped parameter models describing the local dynamics of a tri-trophic chain in a controlled environment is analyzed in detail. The trophic functions characterizing the interactions are defined only by some properties and allow us to treat both prey-dependent and ratio-dependent models in a unified manner.
BUFFONI G, CASSINARI M. P, GROPPI, Maria
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The decline of the trophic level concept
Trends in Ecology & Evolution, 1987The development of the trophic level concept(1) is described and the causes of its failure as a predictive model in ecology are examined. A defence(2) of and modifications to the trophic level concept are reviewed. A trend towards taxonomic food web analysis is identified leading to models that are independent of the trophic level approach.
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A Trophic Level Effect on 137Cs Concentration
Health Physics, 1965Abstract In many animal species, the cesium/potassium ratio in the body is about two to three times higher than the cesium/potassium ratio in their normal diets. Data indicate that this increase ratio is greater with increased potassium intake and is larger in adult humans than in children.
R C, Pendleton +3 more
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2012
Trophic levels are determined by feeding relationships, with basal levels consisting of primary producers or detritus and upper levels based on consumption of these basal levels. Organisms on the second trophic level are referred to as primary consumers, which are in turn consumed by secondary consumers, and so on up a theoretical trophic chain ...
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Trophic levels are determined by feeding relationships, with basal levels consisting of primary producers or detritus and upper levels based on consumption of these basal levels. Organisms on the second trophic level are referred to as primary consumers, which are in turn consumed by secondary consumers, and so on up a theoretical trophic chain ...
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Trophic levels and trophic dynamics: A consensus emerging?
Trends in Ecology & Evolution, 1991There are three clearly different views on trophic levels. The systems-ecological tradition sees trophic levels as relatively discrete and well-defined units whose interactions cannot be derived from interactions between constituent populations. The reductionist population-ecological tradition sees trophic levels as inappropriate abstractions that ...
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